Method of and apparatus for sticking an apex rubber strip on bead rings for use in pneumatic tires

ABSTRACT

A method of and apparatus for automatically sticking an apex rubber strip on bead rings for use in pneumatic tires on mass production basis are provided whereby a number of bead rings may be fed to and disposed on a pair of driving rollers one by one and a continuous apex rubber strip may be fed to the outer periphery of each bead ring. Successive steps of sticking the forward end of the apex rubber strip on the outer periphery of each bead ring, rotating the driving rollers, detecting the arrival of the forward end of the apex rubber strip stuck on the outer periphery of each bead ring at its final position around the bead ring, obliquely cutting the rear end of one turn of the apex rubber strip, re-starting the rotation of the driving rollers and sticking the rear end of the apex rubber strip thus cut on the bead ring, and replacing the bead ring with a new bead ring, are performed automatically.

IJite tates atent 1191 Yonekawa et a1.

[ METHOD OF AND APPARATUS FOR STICKING AN APEX RUBBER STRIP ON HEAD RINGS FOR USE IN PNEUMATIC TIRES [75] Inventors: Hisashi Yoneliawa; Minoru Miyaoka; Norio Abe, all of Tokyo, Japan [73] Assignee: Bridgestone Tire Company Limited,

Tokyo, Japan [22] Filed: Dec. 15, 1971 [21] Appl. No.: 208,237

[30] Foreign Application Priority Data Dec. 19, 1970 Japan 45-113587 [52] US. Cl 156/136, 156/422, 156/460,

[51] Int. Cl 182% 17/34 [58] Field of Search... 156/131, 132, 136, 422, 460,

[56] References Cited UNITED STATES PATENTS 1,651,735 12/1927 Shively 156/422 x 1,759,669 5/1930 Stevens 156/422 X Primary ExaminerClifton B. Cosby Attorney, Agent, or FirmMartin Fleit et a1.

[57] ABSTRACT A method of and apparatus for automatically sticking an apex rubber strip on bead rings for use in pneumatic tires on mass production basis are provided whereby a number of bead rings may be fed to and disposed on a pair of driving rollers one by one and a continuous apex rubber strip may be fed to the outer periphery of each bead ring. Successive steps of sticking the forward end of the apex rubber strip on the outer periphery of each bead ring, rotating the driving rollers, detecting the arrival of the forward end of the apex rubber strip stuck on the outer periphery of each bead ring at its final position around the bead ring, obliquely cutting the rear end of one turn of the apex rubber strip, re-starting the rotation of the driving rollers and sticking the rear end of the apex rubber strip thus cut on the bead ring, and replacing the bead ring with a new bead ring, are performed automatically 2 Claims, 25 Drawing Figures PATENTED JANE? 21974 SHEEY 03 0F 17 PATETH] JANZ 21974 -$NEET USUF W PATENTED JANZZIQM 3,787. 253

WEE? 976? W PATENTEB JAN 2 21974 WEEK 10 0F 1? PATENTE JAN 2 2 m4 SWH HUF 17 PATENTEU 3.787. 263

WEEK 12% 17 PNEMEB JAN 22 1874 mm mar 17 PATENTEQJANZZIHM SEEK HBF 17 PMENTED JAN 2 21974 SEW 16W 17 PATENTEB JAN22I974 WEE? 17W 17 IVIETIIOI) F AND APFA'IUS FOR STICKING AN APEX RUBBER STRIP 0N BEAI) RINGS FOR USE IN PNEUMATIC TIES The present invention relates to a method of sticking ring r. In order to make the folded end y of the carcass ply y in parallel with the outer periphery of the bead ring r, the end of the carcass ply y is bent in two steps so that the bond between the bead ring r and the carcass ply y becomes weak with respect to the tension subjected to the carcass ply y. In order to obviate such disadvantage an annular cavity v having a triangular section is formed by the carcass ply y its end y is filled up with a rubber ring z which is thus stuck on the outer periphery of the bear ring r. This rubber ring 2 is called a stiffner or filler when the region of the above mentioned cavity v is long in the radialdirection of the tire or is called as apex when the region of the cavity v is short in the radial direction of the tire.

Heretofore, it has been the common practice to manually stick the apex rubber ring 2 on the bead ring r with the result that the pneumatic tire could not reliably and efficiently be manufactured on automatic and mass production basis without undesirable problems of manual handlings arising.

The principal object of the invention is to provide a method of sticking an apex rubber strip on bead rings for use in pneumatic tires, which can eliminate the above mentioned prior art problems arising from manual handlings.

A further object is the provision of an apparatus for sticking an apex mbber strip on bead rings for use in pneumatic tires, which is capable of attaining automatic sticking of an apex rubberstrip on head rings and contributing to the tire manufacturing industry.

Preferred embodiments of the present invention are illustrated in the following drawings, in which:

FIG. I shows a section through a bead portion of a pneumatic tire;

FIGS. 2a to 2h show diagrammatically a section of the relative arrangement of the main parts which are essential for the invention and for explaining the-steps of carrying out the methodaccording to the invention;

FIG. 3a is a front elevation of anapparatus according to the invention; i

FIG. 3b shows similarly to FIG. 3a aside elevation;

" FIG. saisarrast 'aavaabsar theiEt'iveEHiifi'gE ment of the mechanism for detachably feeding the bead rings;

FIGS. 5b and 5c are side elevations of detached parts of a detail of FIG. 5a, respectively;

FIG. 6a is a front elevation of the mechanism for rotatably supporting the bead rings; E191- Q 2 shews$ ilaly Q 192.? e191? s sye iqn;

FIG. 7 a is a front elevation of the mechanism for urging the apex rubber strip against the bead rings;

FIG. 7b shows similarly to FIG. 7a a plan view, in which the main parts are shown -in a sectional view;

FIG. 8a is a front elevation of the device for detecting the arrival of the front end of the apex rubber strip stuck on the bead ring;

FIG. Eb shows similarly to FIG.' 8a a side elevation,

in which parts are shown in a sectional view;

FIG. 9a is a front elevation of the cutter for obliquely cutting to apex rubber strip according to the invention; and

FIG. 9b shows similarly to FIG. 9a a side elevation.

- 'x'p'r'aerica'aassaiaait for-carr ing out the method according to the invention will be described with reference to FIGS. 2a to 2h.

In the present invention, a bead ring r is disposed on a pair of driving roller d and d as shown in FIG. 2a and a pressure roller p and driven rollers f and f are slightly urged against that arcuate region of the bead ring r which lies between the driving rollers d and d so as to correct the curvature of the arcuate region of the bead ring r as shown in FIG. 2b.

Near the arcuate region of the bead ring r whose curvature is corrected is arranged a swing lever l which is provided at its front end with a guide roller g. The guide roller g is so mounted that it can be moved upwards and downwards with respect to the bead ring r. Provision is made for a touch roller t which when in contact with the guide roller g is adapted to bite the apex rubber strip s therebetween and feed it towards the bead ring r.

The guide roller g which becomes in contact with the bead ring r as shown in FIG. 2c is rotated in a direction opposite to the feeding direction of the apex rubber strip s to bring back an obliquely cut end i of the apex rubber strip g to the point of contact between the guide roller g and the bead ring r, thereby urging the obliquely cut end i against the arcuate portion of the bead ring r. Subsequently, the guide roller g is freely rotated and a restraining guide piece b is released, thereby permitting a free feed of the apex rubber strip s along the outer periphery ofthe bead ring r as shown in FIG. 2d. At both'sides of the arcute region of the bead ring r whose curvature is corrected are arranged a device for detecting the arrival of the front end i of the apex rubber strip s which is stuck on the bead ring r such, for example, as an air senser a on the one hand and a cutter c for cutting the apex rubber strip on the other hand as shown in FIG. 22.

At first, the pressure roller p together with the driven rollers f and f' are retracted from the bead ring r to a position shown in FIG. 2a. The guide roller g and the touch roller 2 carrying and holding the obliquely cut end i of the apex rubber strip .5 therebetween are located below that arcuate portion of the bead ring r which lies between the driving rollers d and d 'I The cutter 0 occupies an inoperative position.

Then, the bead ring r is disposed .on the driving rollers d and d as shown in FIG. 2a and hence the pressure roller p and the driven rollers f and f' are brought in contact with the bead ring r as shown in FIG. 2b to slidably press down that arcuate portion of the bead ring r which lies between the driving rollers d and d so as to correct the irregularity of the curvature of the arcuate portion of the bead ring r.

Subsequently, the swing lever l is swung upwards to rotate the guide roller g along the arcuate surface of the restraining guide piece b with the aid of a friction wheel w formed integral with the guide roller g. The friction wheel w is urged against the arcuate surface e of the restraining guide piece b to rotate the touch roller t around its own axis and along the periphery of the guide roller g, thus bringing back the obliquely cut end i of the apex rubber strip s into a position near the point of contact between the bead ring r and the guide roller g as shown in FIG. 20.

Thus, the guide roller g serves to stick the obliquely cut end i of the apex rubber strip s on the outer periphery of the bead ring r, particularly on the outer periphery of that arcuate portion which lies between the driving rollers d and d with the aid of the upward force of the swing lever l.

The touch roller t is separated sidewards from the point of contact between the guide roller g and the bead ring r as-shown in FIG. 2c.

The obliquely cut end i of the apex rubber strip s may be stuck on the outer periphery of the bead ring r by means of an adhesive property of the apex rubber strip s or by a rubber cloth wrapping or covering the bead ring r. For this purpose, use may be made of a cementings agent. 1

Then, the restraining guide pie'ce b becomes inoperative as shown in FIG. 2a. That is, the friction wheel w is separated from the arcuate surface e of the restraining guide piece b to permit a free rotation of the guide roller g. The subsequent rotation of the driving rollers d and d makes it possible to guide that portion of the apex rubber strip s which succeeds the front end i' of the apex rubber strip s stuckon the bead ring r along the outer periphery of the bead ring r through the space between the driving roller d and the bead ring r and press it against the bead ring r and stick on the latter as shown in FIG. 2d.

If the front end i of the apex rubber strip s stuck on the bead ring r arrives at a position which is about one half the periphery of the bead ring r, the swing lever I together with the guide roller g begin to swing downward until the guide roller g reaches its retracted position shown in FIG. 2e. Then, the front end i of the apex rubber strip s arrives at the air senser a. In this position, the cutter c occupies its elevated position ready to performits cutting operation.

If the front end i of the apex rubber strip s together with the bead ring r have rotated one turn and passed over the driving roller d, the air sensor a arranged near the driving roller d and across the passage of the front end i of the apex rubber strip 5 serves to detect the arrival of the front end i to produce a detection signal which causes the driving rollers d and d to be stopped for a duration from the step shown in FIG. 2e to the step shown in FIG. 2f.

Then, the cutter c in the elevated position is operated to cut that portion of the apex rubber strip s which lies between the driving roller d and the guide roller g as shown in FIG. 2f.

This cutting position is determined such 'that the rear end of the apex rubber strip s cut coincides with the front end i thereof.

Then, the cutter c is moved downwards and becomes inoperative and the rear end i" of the apex rubber strip s and the front end i thereof hang down from the driving roller d and guide roller g, respectively, as shown in FIG. 2g. Then, the driving rollers d and d are operated again to reliably stick the apex rubber strip s around the bead ring r as shown in FIG. 2h.

Subsequently, the driving rollers d and d are stopped and the pressure roller p and the driven rollers f and f are again moved to their retracted positions shown in FIG. 2a. Then, the bead ring r'is removed from the driving rollers d, d and a new bead ring r is disposed on the driving rollers d and d. Then, the above mentioned steps are repeated to stick the succeeding apex rubber strip s on the new bead ring r.

An apparatus for carrying out the above mentioned method according to the invention will now be described with reference to FIGS. 3 to 9.

The apparatus according to the invention comprises a frame work 1 which is provided at its front side with the driving rollers d and d adapted to be driven through a transmission mechanism (not shown) by an electric motor 2.

The pressure roller p slightly pressing downwards that arcuate portion of the bead ring r which lies between the driving rollers d and d and the driven rollers f, f are rotatably mounted on a supporting frame 3. The supporting frame 3 is adapted to be moved upwards and downwards and also inclined backwards. Provision is made for an adjustable screw 4 which is capable of adjusting the upward and downward movements of the pressure roller p with respect to the supporting frame 3.

The frame work 1 is provided at its front side and at substantially center thereof with a guide wheel 5 for guiding the apex rubber strip s formed, for example, by an extruder (not shown) and with a touch roller 6. The guide wheel 5 and the touch roller 6 are rotatably mounted on a bracket 7 whose inlet side is provided with a pair of guide poles 8. The guide roller g adapted to stick under pressure the apex rubber strip s on the outer periphery of the bead ring r is rotatably mounted on the one end of bifurcated arms ofa Y-shaped swing lever l pivoted at the top end of the frame work 1. The end of the outer bifurcated arm of the swing lever l is brought into engagement with the end of one arm of a bell crank 9 pivotally mounted at the frame work 1. The end of the other arm of the bell crank 9 is driven by a pressure cam 10 pivotally mounted on the frame work 1. The bell crank 9 is always brought into engagement with the pressure cam 10 by means of a spring 11.

The restraining guide piece b which causes the guide roller g to freely rotate only when the guide roller g is positioned near the bead ring r is pivotally mounted at its bent portion on the frame work 1 and is formed in bell crank shape whose vertical arm is provided at its front side with the arcuate surface e. The free end of the horizontal arm of the restraining guide piece b is brought into engagement with a hydraulic lifter l3 pivotally mounted on a bracket 12 so as to separate the vertical arm from the guide roller g.

I In drdno move the cutter c upwards and downwards between the guide roller g and the driving roller 

1. A method of sticking an apex rubber strip on bead rings for use in pneumatic tires comprising the steps of disposing a bead ring on a pair of driving rollers and supporting said bead ring between said driving rollers on the one hand and at least one pressure roller which can correct unevenness of the curvature of that arcuate portion of said bead ring which lies between said driving rollers on the other hand, sticking an obliquely cut end of an apex rubber strip on the outer periphery of said arcuate portion of the bead ring with the aid of a guide roller movaBle between a first position where said guide roller is urged against the outer periphery of said arcuate portion of the bead ring and a second position where said guide roller is retracted from said first position, rotating said bead ring by said driving rollers to stick that portion of said apex rubber strip which succeeds said obliquely cut end stuck thereon and delivered through said guide roller on the outer periphery of said bead ring and then retracting said guide roller to said second position, detecting the arrival of said obliquely cut end stuck on the apex rubber strip at the outer periphery of said arcuate portion of the bead ring to stop said driving rollers and then obliquely cut that portion of the apex rubber strip which lies between the guide roller and the driving roller, re-starting the rotation of said driving rollers to stick the apex rubber strip thus cut on the bead ring and releasing said pressure roller, and finally replacing said bead ring with said apex rubber strip stuck thereon with a new bead ring.
 2. Apparatus for sticking an apex rubber strip on bead rings for use in pneumatic tires, comprising means for rotatably supporting a bead ring and consisting of a pair of driving rollers arranged along the outer periphery of said bead ring and spaced one from the other and at least one pressure roller adapted to slightly increase the curvature of that arcuate portion of said bead ring which lies between said driving rollers; means for urging an apex rubber strip against said bead ring and consisting of a guide roller for guiding said apex rubber strip to be stuck on the outer periphery of said bead ring, a touch roller which is in engagement with said guide roller and adapted to be rotated in reciprocation along the periphery of said guide roller, and an operating mechanism including a restraining guide piece and adapted to move said guide roller from a first position where said guide roller makes contact with the outer periphery of said bead ring under pressure to a second position where said guide roller is retracted from the outer periphery of said bead ring, said guide roller being permitted to freely rotate during the movement of said guide roller towards said first position and caused to be rotated in a direction such that the obliquely cut end of said apex rubber strip clamped between said guide roller and said touch roller is retracted; means for detecting the arrival of that end of said apex rubber strip which is stuck on the outer periphery of said bead ring at said arcuate portion of the bead ring in response to the rotation of said driving rollers; and a cutter for obliquely cutting that portion of said apex rubber strip which lies between said guide roller located at said second retracted position and said driving roller. 